Why isn't the shine/gloss showing on the character when I render?
The problem is just what I expected,
There are no lights.
You are rendering a closed space with no lights. Of course, it's not gonna be visible in the render.
As you can see in the image below adding just four point lights set to about 400watts power helped so much. There is nothing wrong with your material you just don't have any lights for the material to reflect.
Also, the table cloths and some other things are pink because you didn't pack the image textures in the blend file you shared.